The tire mounting and demounting bar generally relates to tire changing machinery and more specifically to a bar that pulls the tire bead from a wheel rim.
In bays and shops across the land, numerous tires are changed from wheels. Tires have tread that meets the road and sidewalls perpendicular to the tread. Tires have sidewalls upon both sides of the tire that extend partially towards the center, or towards a rim. At the innermost portion of the sidewall, the tire has an encased bead. The bead is a thickened portion of the sidewall surrounding metal wire. Now a wheel generally has two parallel and spaced apart rims upon its circumference. The rims have a greater diameter than the substantial portion of the tire's inner circumference.
Tire changing involves mounting a tire upon a wheel or removing a tire from a wheel. For mounting a tire upon a wheel, the wheel is clamped into a fixed position. One bead is placed over a rim as much as possible and then mechanical device manipulate the remainder of the bead over the rim. The beads are designed to remain a constant diameter when a wheel rotates as on a vehicle, or a motorcycle, even as it goes faster. The second bead undergoes the same procedure. Inflating the tire then seats both beads against their respective rims. For removing a tire from a wheel, the wheel is clamped again into a fixed position. The tire is partially deflated and then a mechanical device is inserted between a bead and a rim. The mechanical device stretches a small portion of the bead over the rim. Continuing to operate, the mechanical device then lifts the remainder of the bead over the rim. As before, the second bead undergoes the same demounting procedure.
Wheels are used on many vehicles. On utility vehicles, the appearance of wheels matters less so than on personal vehicles. For automobiles, motorcycles, and some boat trailers, the wheels and their appearance have high importance to their drivers. People often place great emphasis on the appearance of wheels as part of their self image. The after market in wheels of all kinds has enormous size. Often, people seek out shiny or novelty wheels to customize vehicles. In particular, motorcycles have shiny wheels including spokes and rims.